Thanks, this and madisound is where I am getting them from. Decided not to get the uber-performing and uber-expensive Duelund's and go with Mundorf Supremes instead.
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Inching closer to a Summit X
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Thanks, this and madisound is where I am getting them from. Decided not to get the uber-performing and uber-expensive Duelund's and go with Mundorf Supremes instead.
BTW, here are three blogs I found very useful in my research - audiocircle, humblehifi and laventure
I found the 1839 easier to install, they are axial version of 1837. Use them to bypass all the polypropylene foil capacitors, 10nF.
I also found that using 630V 10nF Wima MKS-4 brought another level of clarity, I have put them parallel to MKP1839. Even better 1000V ones.
I have noted that the values in schematic did not correspond 1:1 to what was really in the crossover, e.g. 5uF in the schematic being 4.7uF in the actual crossover.
For 47 you're closer with 2x22 + 3.3.
Try to match as closely as possible what's in the actual crossover, thus you will avoid unpleasant surprises.
Good luck and have fun!
OK will look for it
This is not the case with the Odyssey.
The reason I left the 3.3 out is because it's not far away from 22; I've been told the rule of thumb is they are all either very close in value, or very very far apart, to the tune of 50X!
That I agree with... Thanks again.
tsv_1
Well-known member
Sorry to stick my nose in here... but your comment elevated my eyebrows a bit. While there are rules of thumb for the effectiveness of broad-spectrum noise filtering when using multiple caps in a noise suppression configuration, that doesn't hold true for caps used as a critical element in a typical LCR crossover. Variation in the value of C away from what the original design calls for will directly impact the intended cross over point. That said, there's nothing to stop anyone from playing around with values to see how the cross-over change impacts integration between drivers (but generally speaking, designers pick component values carefully based on how speakers are engineered).
I haven't looked at the history of your discussion above, so my apologies if my comment is out of place.
Spectral -- please keep us in the loop on how this turns out.... I am not an EE but modifying odysseys definitely interests me.... since I also own a pair... 
You will have to give a 'post' change review... and use words like 'bloom'...'decay'....'pace' etc.... hahaha.... But, seriously am very interested in this wacky adventure you are on....
You will have to give a 'post' change review... and use words like 'bloom'...'decay'....'pace' etc.... hahaha.... But, seriously am very interested in this wacky adventure you are on....I don't think I agree with you here... the problem is unpredictable impedance interactions, which can be deleterious. If it were as simple as just stacking up caps I would have done it already. I am not theorizing here, I know this from first-hand experience - years ago I did stack them up willy nilly in front of a tweeter; and the result? dead-sounding tweeter. You don't just add up capacitor values like that to get what you want; it requires a lot of thinking.
It depends; notice, I am within the 10% tolerance of the stock capacitor currently in place. And the tolerance of what I putting in is 3% tops.
Spectral -- please keep us in the loop on how this turns out.... I am not an EE but modifying odysseys definitely interests me.... since I also own a pair...
Yeap, once done I will start a new thread on this. The O's have a very clear achille's heel, and it's the caps in the crossover - for starters, electrolytics for the woofers; ouch. The resistors appear to be first rate, but I did also plug in some Mundorf M-Resist Supremes in the panel crossover, and there is no audible effect whatsoever. Finally, I know nothing yet about the inductors, but they appear OK. I am proceeding with one capacitor at a time with brief listening tests - I expect any cap to break in over 300 hrs, so I am looking for really offensive, obviously detrimental changes
This is getting off topic, so I am going to start a new thread on the Odyssey mod... Besides ,there appears to be a lot of interest from other owners who are looking for the diagram... And I also have some initial pictures to share...
Gordon Gray
Well-known member
Peter,
Since you'll be inside the woofer module, see my thread in the "Tweaks" section on what I did with my SL3's. Specifically applying "Road Kill" or equivalent to the inside of the cabinet and driver ribs. Attenuates cabinet / driver vibrations. Quite audible, quite positive, and quite cheap.
Good luck with your modified "O's".
Gordon
Since you'll be inside the woofer module, see my thread in the "Tweaks" section on what I did with my SL3's. Specifically applying "Road Kill" or equivalent to the inside of the cabinet and driver ribs. Attenuates cabinet / driver vibrations. Quite audible, quite positive, and quite cheap.
Good luck with your modified "O's".
Gordon
Perfect! I was looking for something like this as well; thank you so much
tsv_1
Well-known member
I'm not going to argue basic electronics with you. If a design calls for 47uF and you install 44uF, then you are likely to be out of range wrt the intent of the original design. The problem with "stacking caps" is that you can introduce unintended inductance (i.e. wiring multiple caps into a tight area without considering lead length). However, if implemented carefully, it should be fine.
At any rate, good luck with your mods.
Bernard
Well-known member
Todd, I tend to agree with your thinking (but not sure inductance would be an issue). Also, if the designers used 10% tolerance caps that were in fact 9% under (42uF in your example), and Spectral replaced them with caps that were 2% over (48 uF in your example), the end result would be a value 14% higher than the original, and this would really impact the crossover point.
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Gordon Gray
Well-known member
Thank you - "likely"... it's possible they were looking for a 45uF and eventually selected a common 47uF... We'll never know...
tsv_1
Well-known member
Cool. BTW, I think it's great that you're digging into this and making these mods. No better way to learn what works and what doesn't. I've built MOSFET audio amps, low noise Mic pre-amps and other gear in the past. Learned a ton... especially how easy it is to touch 120v rails.
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Bernard
Well-known member
Babe in the woods. I have touched 240v rails !Learned a ton... especially how easy it is to touch 120v rails.
tsv_1
Well-known member
Pffff... kid's play... have you ever been bitten by a large colo(u)r TV flyback transformer? A hair-raising proposition to say the least.
roberto
Well-known member
I almost lost my index finger and my thumb when I was working at TV Channel 7. There was an AGC mechanical and because of a debris, was not following the the right track, and I put my right hand with the transmitter on, the station was out of the air for over 20 minutes, and I was sent direct to the hospital for a month treatment with a severe burn. You should see my hair then...
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